namespace a1{
	//CapitalizeString首字母大写
	type CapitalizeString<T  extends (string | number)> = T extends string? Capitalize<T>: T
	type a1 = CapitalizeString<'handler'>       // Handler
	type a2 = CapitalizeString<'parent'>        // Parent
	type a3 = CapitalizeString<233>             // 233
	let a:a1 = 'Handler'
}
